Noticed a huge maple in Portland's Laurelhurst Park with a bark wound that's been healing for years

Was walking my route through the park last week and saw this massive maple that must have taken a car bumper hit like 5 years ago based on the callus growth, but whoever pruned it left the wound shape kind of jagged instead of rounding it off. Has anyone else seen municipal trees with old wounds that healed way slower because of bad cuts?

2 comments

2 Comments

jackson.jenny27d agoMost Upvoted

Actually the wound shape thing is a common misunderstanding. Arborists actually recommend NOT rounding off wounds anymore because trees can't heal like skin does. They compartmentalize the damage instead of growing new bark over it. Leaving it jagged doesn't really slow the process since the tree builds callus tissue from the cambium layer which is alive and growing around the injury. The real issue with that maple is probably the damaged bark being too big for the tree to close up quickly, not the cut shape. Portland parks does a decent job but some of those older trees just take forever to seal off big wounds no matter what you do.

ryang7727d ago

Actually bought into the old-school thinking for years that you had to round off wounds to help trees heal faster. Read that same stuff in DIY tree care guides online and believed it until I saw a side-by-side comparison of two wounded oaks in my own neighborhood - one rounded off, one left jagged - and the jagged one actually had better callus growth after three years. Your explanation about compartmentalization makes total sense now, trees really are just building walls around the damage instead of trying to grow new bark over it like we do with skin.